Process for preparing durable-press or wash-wear fabrics which can be whitened with acidic optical brighteners

ABSTRACT

This invention consists of the preparation of durable-press fabrics with basic moieties crosslinked into the fabric. As a consequence of these basic moieties, these fabrics can now absorb acidic optical brighteners. Heretofore, crosslinked cotton fabrics showed poor absorption characteristics for acidic optical brighteners. This fabric basicity is achieved by the use of reactive alcohol additives containing amine groups such as diethanolamine, triethanolamine, monoethanolamine, and 2dimethylaminoethanol.

United States Patent 1191 Harper, Jr. et al.

[ PROCESS FOR PREPARING A DURABLE-PRESS OR WASH-WEAR FABRICS WHICH CANBE WHITENED WITH ACIDIC OPTICAL BRIGHTENERS [75] Inventors: Robert J.Harper, Jr.; Gloria A.

Gautreaux, both of Metairie; Eugene J. Blanchard, New Orleans, all ofLa.

[73] Assignee: The United States of America as represented by theSecretary of Agriculture, Washington, DC.

22] Filed: Jan. 24, 1972 [21] Appl. No.: 220,415

52 US. Cl 8/18, 8/1 w, 8/17, 8/31, 8/100, 8/185, 8/186, 117/335 T [58]Field of Search". 8/185,17,18, 31, l W, 186,

[56] References Cited UNITED STATES PATENTS 2,950,553 8/1960 'l-lurwitz8/185 [111 3,795,480 14 1 Mar. 5, 1974 3,663,159 5/1972 Gordon 8/1853,407,026 10/1968 Mauldin 8/185 2,957,746 10/1960 Buck et al 8/1853,658,457 4/1972 Blanchard et al 8/1 X 3,702,230 11/1972 8/31 XBlanchard et al .7

Primary Examinerl-lerbert B. Guynn Attorney, Agent, or Firm-M. HowardSilverstein [57 ABSTRACT diethanolamine, triethanolamine,monoethanolamine,

and 2-dimethylaminoethanol.

7 Claims, N0 Drawings PROCESS FOR PREPARING DURABLE-PRESS R WASH-WEARFABRICS WHICH CAN BE WHITENEI) WITH ACIDIC OPTICAL BRIGHTENERS Anon-exclusive, irrevocable, royalty-free license in the invention hereindescribed, throughout the world for all purposes of the United StatesGovernment, with the power to grant sublicenses for such purposes, ishereby granted to the Government of the United States of America.

This invention relates to treatments which impart wrinkle resistance tocellulosic textile materials. In particular,-it relates to a method bywhich cotton fabrics may be finished so that they will be wrinkleresistant and will have characteristics that will absorb acidic opticalbrighteners normally used on basic fibers such as ric is then dried andcured in the usual manner. The

crosslinked fabrics arethen laundered to yield a durable-pre s s fabricwhich contains amine groups crosslinked into the fabric matrix. As aconsequence of these basic groups, the fabric now possesses goodaffinity for acidic optical brighteners.

j Various amounts and types of alcohol amines can be used as reactiveadditives for the purpose described. In general, the effective rangestudied has been from about 0.5 percent to about percent of the alcoholamine in the pad bath. The preferred range of operation appears to befrom about 1-2 percent. The higher amounts of amine in the formulationsometimes lead to discoloration problems and this is another reason forgiving preference to low concentrations in the pad bath. A variety ofalcohol amines have been utilized. From the viewpoint of brighteneruptake, there are some indications that the amount of brightenerabsorbed seems to increase with the basicity of the amine fixed on thefabric. In this respect, tertiary amines are better than secondaryamines and secondary amines are better than primary amines. Furthermore,from the viewpoint of fabric discoloration, tertiary amines seem tocause less fabric discoloration than secondary amines which in turn seemto cause less discoloration than primary amines. Examples of thetertiary amines used in this work are triethanolamine and 2-'dimethylaminoethanol. An example of the secondary amine isdiethanolamine, and an example of a primary amine is monoethanolamine.

The preferred crosslinking agent with this method 7 appears to bedimethylol dihydroxyethyleneurea. Al-

though other agents are also effective, the preceding agent isparticularly effective because it has four N- methylol groups availablefor crosslinking. As a result, if one methylol moiety is used inreaction with the reactive additive, three other sites are stillavailable for crosslinking cotton. As a consequence, it is possible toobtain fabrics with good durable press ratings and wrinkle recoveryvalues and with a certain amount of amine groups attached to the fabric.Because of these amine groups, the fabric has a-basic character and willnow absorb acidic optical brighteners.

Thus, one should consider three cotton fabrics. One fabric is untreated,the other is crosslinked in a conventional manner using crosslinkingagent, metal salt catalyst and no reactive amine additive. The thirdfabric is crosslinked using crosslinking agent, metal salt catalyst,reactive alcohol amine and sufficient acid to neutralize the alcoholamine. Examples of the alcohol amines have been previously mentioned.The fabrics are laundered and are then treated in a bath containing theacidic optical brightener. The fabrics are then rinsed and laundered.The fabrics are inspected under regular and UV light. The samplecrosslinked with no amine additive shows poor absorption of opticalbrightener. The untreated control shows fair to good absorptiondepending upon the specific optical brightener. On the other hand, thefabrics with the amine additives show excellent absorption of opticalbrightener. As a consequence, these fabrics appear white under regularlight while the crosslinked fabrics without the alcoholic amine additiveare somewhat off-colored. Under UV light, the fluorescence due toabsorption of brightener can be readily observed. Thus the crosslinkedcontrol looks grey while the untreated control may be a fair to somecases, they absorb the acidic optical brightener to a greater extentthan the untreated cotton control. This can be observed not only byvisual inspection under regular and UV light but also by measurement ofthe fluorescence of the samples using a spectrofluorometer. Thus, withone acid brightener, the crosslinked samples with triethanolamineadditive had from 87-143 percent of the fluoresence of the untreatedcotton. By contrast, the crosslinked control with no amine additive hadonly 7 percent of the absorption of the untreated control. These resultsreadily illustrate the effectiveness of this method in producing acrosslinked fabric which will absorb optical brighteners.

It is believed that this process represents a significant improvement inthe state of the art for several reasons. First, it produces acrosslinked cotton fabric with good affinity for acidic opticalbrighteners. Because normally crosslinked fabrics absorb opticalbrighteners of any type poorly, they tend to become grey and dingy aftera certain amount of use. Because the amine groups are permanentlyattached to fabrics, the fabrics may be whitened at any time by theapplication of a bath containing an acidic optical brightener.

A further advantage in this method of whitening fabrics aftercrosslinking is that while brighteners can. be added in the bath withcrosslinking agents, many lose much of their effectiveness under thesevere curing conditions (temperature from l50170C) employed in curingresins. As a consequence, better and more efficient use ofthe'brightener can be obtained if the whitener is applied subsequent tothe cross-linking process. Heretofore, this has not been possible.However, in this process, whitener uptake can be achieved both by a bathapplication equivalent to mild dye conditions or by routine padding anddrying conditions of the type frequently used to apply a top softener tofabric.

The major advantage would, however, appear to be in the possibility ofwhitening fabrics or garments at any time and as frequently during thenormal use cycle as the housewife or the laundry so desires. The onlyagents required are a suitable acid brightener, a source of mild acid(such as household vinegar), and water. The operation can be repeated onthe garment whenever the whiteness from the previous application hasdisappeared due to dissipation of the brightener on fabric caused byremoval through repeated laundering, bleaching, heat or light.

The agents needed to modify the fabric in this particular manner arerelatively inexpensive, easily added to finishing baths, and can be usedin the bath in relatively small quantities.

In general terms, the process of this invention starts with theincorporation of the alcoholic amine in the normal pad bath solutiontogether with sufficient acid to neutralize the basicity introduced bythe amine. From this point on, the fabric is finished in a standardmanner according to contemporary textile practice. This method can beused with a number of textile formulations, the only requirement beingthat an appropriate amount of water be replaced by hydroxyamine additiveand its neutralizing acid equivalent. The method is readily applicableto either precure or postcure one-bath one-step treatments. Moreover,for demonstration purposes, it has been applied to other finishingmethods such as the moist cure or easy cure methods. The fabrics arethen laundered. At this point, the whitener can then be applied usingmild dye bath conditions or by repadding and drying the fabric. Garments can be treated at any time during their use cycle by thehousewife, laundry or garment maker. Furthermore, the operation can berepeated whenever it would appear to be advantageous during the lifecycle of the garment.

A number of hydroxyamines have been employed as reactive additives.Typical of such agents are triethanolamine (A) diethanolamine (B)monoethanolamine (C),

and Z-dimethylaminoethanol (D) Other agents can easily be visualized.The only requirements would be that the compound carry a hydroxyl groupfor reaction with the crosslinking agent and a basic amine moiety forimparting a basic character to the fabric.

Although the description to this point concerns the use of all-cottonfabrics, applications could be made to blended fabrics as well. Blendsof wool-cotton, wool, nylon and cotton or cotton-nylon might beespecially susceptible to improvement since the acid brighteners wouldbe expected to be helped by these treatments. This is because thebasicity imparted to the cotton component together with the naturalbasicity of these fibers should make these fabrics have good absorptioncharacteristics for the acidic brighteners since all components would beactivated. This method has also been applied to polyester-cottonfabrics. In this case, only the cotton component :is activated byerosslinking in the reactive amine alcohol. However,-the overall fabricis considerably whiter due to the absorption of the acidic opticalbrightener when compared with the polyester-cotton fabric with aconventional crosslinking treatment.

To summarize, this invention can best be viewed as a .process forimparting receptivity of acid optical brighteners to crosslinked cottonfabrics. Normally crosslinked cotton fabrics have poor receptivity foracidic optical brighteners. The improvement consists in the use ofhydroxy amines as coreactants In normal crosslinking systems. As aconsequence, crosslinked fabrics are obtained containing pendant aminegroups fixed on the fabrics. Whitening procedures can now be applied tothese-fabrics using acidic optical brighteners,

which would be substantive to a basic substrate. Cotton crosslinked inthe normal manner and occasionally untreated cotton fabrics have poorsubstantivityor affinity for acidic optical brighteners.

Only the basic formulations have been used in these examples. Variationsusing softeners, wetting agents, polymer additives and various finishingsystems are readily accessible for anyone skilled in the art of textilefinishing.

EXAMPLE 1 One set of cotton printcloth was padded with a solutioncontaining 9 parts dimethylol dihydroxye thyleneurea, 0.5 parts zincnitrate hexahydrate and 90.5 parts water. The fabric was dried for 7minutes at 60C and cured for 5 minutes at C. The fabric was thenlaundered and tumble dried.

A second set of cotton printcloth was finished with modifiedformulations and cured in the same manner. The modifications consistedof replacing equivalent number of parts of water with the same number ofparts of base and neutralizing with acid to maintain pH at leass than 5The bases used were triethanolamine (0.5, l, 2, 3, 5 parts in thepadding solution); diethanolamine l 2, 3, 5 parts in the paddingsolution), monoethanolamine (I, 2, 3, 5 parts in the padding solution),and 2- dimethylaminoethanol (0.5, l, and 3 parts in the paddingsolution). After the various samples treated with the modifiedformulation were prepared and laundered, they represented a series offabrics in which the fabrics had good wash-wear or durable-pressappearance, wrinkle recovery values ranging from 250 to 280 and graftson the fabric containing these attached amine groups. The presence ofthese amine grafts was indicated by the fact that these reactiveadditives led to an increase both in total fabric add-on as well as inbound nitrogen on the fabric.

Small swatches of two sets treated above together with an untreatedcotton control were then immersed in a bath prepared from 0.5 percentFluorescent Brightener 134 [Color Index Name: 1968 Edition w AmericanAssociation of Textile Chemists and Coloriss Section D, pp 1-128] and99.5 parts water heated to 3035C. The samples were agitated in this bathat this temperature for 30 minutes and then the temperature wasincreased to 4045C for an addi' tional period of 30 minutes. The sampleswere then rinsed seven times with distilled water and heated to 35C for5 minutes. One swatch of each sample was then laundered on the wash-wearcycle using warm water.

The samples were then inspected under regular light, UV light, and byuse of the Farrand Spectrofluorometer. Very little difference could bedetected between the series of samples given a regular wash and theremaining series of samples washed only in distilled water.

Under regular light, the samples which appeared whiter than thecrosslinked control were those samples in which triethanolamine or2dimethylaminoethanol were used as reactive additives. At low levelconcentrations with diethanolamine, improvement in whiteness relative tothe crosslinked control was noted, but at high level concentrations,there is a distinct lack of improvement due to discoloration on curingarising from the amine. With monoethanolamine a distinct discolorationarises right from the start so a practical application using thisreagent would seem to depend upon the elimination of color duringcuring. The fact that the fabrics with the amine additives were whiterthan the crosslinked controls reflects the effectiveness of the overallprocess of using an acidic optical brightener on a basic fabric.

These results were further demonstrated by the inspection of thesefabrics under UV light. Under UV light, the cross-linked control isgrey, the untreated control fluoresces a bright white and all thesamples with the amine crosslinked into the fabric fluoresce and appearto be white similar to the untreated control fabric. This is anotherdistinct indication that by the use of an acidic optical brightener(such as would normally be used on a basic fabric, such as wool), oneobtains good absorption of the brightener even though the fabric iscrosslinked. This absorption is achieved because the fabric has hadbasic groups crosslinked into the fabric structure.

As a further demonstration of the effectiveness of this approach, thesamples were measured for fluorescence using a FarrandSpectrofluorometer. The fluorescence was measured at 445 mp, which wasthe peak amines showed absorption ranging from 82-94 percent of theuntreated control. The fabrics treated with DMDHEU and secondary aminesshowed absorption from 6077 percent of the untreated control. Thefabrics treated with DMDHEU and primary amines showed absorption from3445 percent of the untreated control. Under the circumstances, thecross linked control with no amine additive showed absorption from only10-12 percent of the untreated control. These results clearly indicatethe effectiveness of the amine additives in producing fabrics with goodabsorption characteristics for acidic optical brighteners. Furthermore,Table l readily shows that the amine additives are very effective atrelativelylow levels of amine inthe pad bath solutions. With only 1%triethanolamine in the pad bath solution, fluorescent absorption was 83percent of the untreated control.

This experiment readily demonstrates the effectiveness of this approachin improving the whiteness and absorption of fluorescent brighteners bycrosslinked fabrics.

TABLE 1 FLUORESCENCE OF CROSSLlNKED FABRICS TREATED WITH FLUORESCENTBRIGHTENER 134 The fluorescence of the untreated cotton fabric was takento be and everything else is reported relative te this.

EXAMPLE 2 Swatches of the samples prepared in Example 1 were treatedwith a bath containing an acidic optical brightener of the Stilbenetype. The bath contained 0.5 parts of the acid brightener and 99.5 partswater. The pH was adjusted from 7 to 4.5 using dilute HCl. The fabricswere immersed in the bath at 35-38C for a period of 30 minutes; thetemperature was raised to 52C for a period of 30 minutes and thenallowed to cool to 40C over a period of 30 minutes. The fabrics werethen washed in distilled water seven times and then heated to 40 indistilled water, rinsed and tumble dried. With respect to the whitenessof the final fabrics, those treated with tertiary amines (that is,triethanolamine and 2- dimethylaminoethanol) and crosslinking agent weredistinctly whiter than the crosslinked control and somewhat whiter thanthe untreated cotton. The samples treated with DMDHEU and diethanolaminewere whiter than the crosslinked control particularly in the case inwhich a lower level of amine was used in the pad bath. With the higherlevels of secondary amines and the samples treated with primary amines,the discoloration arising on curing tended to overcome the effect of theabsorption of brightener.

Likewise, inspection of these samples under UV light showed the distincteffects of the grafted amine additives on the absorption of the acidicoptical brighteners. Thus, the crosslinked control appeared to be grey,and the untreated cotton showed fair absorption of brightener andfluoresced. On the other hand, the samples with amines crosslinked inthe fabric showed strong absorption of optical brightener and strongfluorescence under UV light.

This strong absorption of brightener likewise clearly demonstrates theeffectiveness of this procedure in producing a crosslinked fabric whichshows good absorption of an acid optical brightener. The contrast withthe crosslinked control is marked. A further example of theeffectiveness of this procedure can be found by measuring thefluorescence of the samples using a Farrand Spectrofluorometer. As theresults in Table II indicate, the fluorescence of the samples withtertiary amines crosslinked into the fabric ranged from 87-143 percentof the untreated cotton. With the secondary amines crosslinked into thefabric, the fluorescent values were 65-83 percent of the untreatedcontrol. Similarly, with the samples with primary amines crosslinkedinto the fabrics, fluorescent values were 41-54 percent of the untreatedcotton. By contrast, the crosslinked control with no amine additive hadonly 4-7 percent of the absorption of brightener as the untreated cottoncontrol. Furthermore, as the figures in Table II show, excellentabsorption of optical brightener was achieved using a were padded with asolution prepared from 0.75 parts Fluorescent Brightener I25, 1 partglacial acetic acid; and 98.25 parts water. After this the fabrics wererinsed thoroughly in distilled water (8 washings) and dried, and theywere inspected under regular and UV light. While the crosslinked samplewith no additive was discolored, the samples with the triethanolamine,diethanolamine, and 2-dimethylaminoethanol were whiter both with respectto the crosslinked control and the un- 0 treated cotton fabric.Furthermore, a parallel effect which 'a high level of triethanolaminewas crosslinked into the fabric was taken to be 100 percent On thisbasis, as indicated in Table III, the crosslinked control showed only 10percent of the fluorescent value as the control while the untreatedcotton showed 24 percentv 25 of the fluorescent value of the control. Onthe other 58-78 percent and those with primary amines crossrelativelylow level of additive agent in the padding solution.

TABLE II hand, while the samples with tertiary amines crosslinked intothe fabric showed fluorescent values ranging up to 76-100 percent, thefabrics with secondary amines crosslinked into the fabric showed valuesfrom linked in the fabric had values from 28-46 percent of the control.I

The results clearly show that fabrics treated by this process can beselectively whitened with an acidic brightener using an afterwash typeof padding conditioner. The fabrics treated with crosslinking agent andamine additives absorb the brightener to a much ABSORPTION OF STlLBENETYPE ACID BRIOHTENER BY BASIC FABRICS 7r Amine All samples were given aconventional pad-dry-cure treatment as described in xams 2 Fluoresceneeef ilntreated eo tto n was taken as with everything elsereportedrelative to this. Fluorescence was measured at 450 mp.

EXAMPLE 3 Swatches of samples of the fabrics from Example 1 greaterextent than the crosslinked control or, for that matter, the untreatedcotton fabric.

TABLE III FLUORESCENT MEASUREMENTS OF ALL COTTON FABRICS TREATED WlTHFLUORESCENT BRlGHTENER 125 Y "ln this case, the fluorescent value of thesample cross-linked in the presence of 5% triethanolamine was taken as100%. Fluorescence was measured at 445 mu.

EXAMPLE 4 A sample of 50-50 polyester-cotton (a blend containing 50percent cotton and 50 percent polyester) was treated with 9 partsdimethylol dihydroxyethyleneurea, 0.5 parts zinc nitrate hexahydrate,and 90.5 parts water. The fabric was dried for 7 minutes at centBrightener 134). The procedure used in Example 1 was employed in thiscase. An observable improvement was noted in the whiteness of thefabrics under either regular or UV light for the samples with thetertiary amines (triethanolamine and 2- dimethylaminoethanol)crosslinked into the fabric. The improvement is not as great as with allcotton fabrics TABLE W '50-50 POLYESTER-COTTON FABRIC, Treated withFluorescent Brightener 134 7r 7! Amine in Type of Amine DMDHEU Pad Bathin Pad Bath Fluorescence 9 0 0 29 9 0.5 Triethanolamine 9 1.0Triethanolamine 56 9 3.0 Triethanolamine 73 9 0.5 Z-Dimethylaminoethanol9 1.0 2-Dimethylaminoethanol 76 9 3.0 Z-Dimethylaminoethanol 76Untreated polyester-cotton 76 100 Untreated cotton C and cured for 5minutes at 160C. The fabric was then laundered and tumble-dried. Othersamples of the same fabric were finished with modified formulations andcured in the same manner. The modification consisted of replacing anequivalent number of parts of 55 water with the same number of parts ofbase and sufficient neutralizing acid to maintain the pH of the treatingbaths at less than 5. The bases used were triethanolamine (0.5, 1, and 3parts in the padding solution) and 2-dimethylaminoethanol (0.5, 1, and 3parts in the padding solution). After these samples were prepared andlaundered, they represented a series of fabrics. in which the fabricshad good wash-wear or durable-press appearance, high wrinkle recoveryvalues and grafts on the fabrics containing the previously mentionedamine groups. Samples of these fabrics were then treated with a bathcontaining an acidic optical brightener (Fluoresbut as shown in Table1V, the amount as measured by the Farrand Spectrofluorometer issubstantial. Indeed at the high level of amine treatment, the'value ofthe fluorescence of these fabrics was close to that of the untreatedpolyester-cotton. It might be noted that the polyester fiber is madewith an optical brightener in it which is a factor which tends toaverage out the results with blended fabrics.

Samples of the above fabrics were also padded with FluorescentBrightener using the procedure reported in Example 3. The samples werethen checked using the Farrand Spectrofluorometer and the results arereported in Table V. it can be readily observed in Table V that thefluorescent values of the crosslinked samples with amine additives aresubstantially higher than for the control samples with'no amine additivein the finishing formulation. 7

' TABLE v 50-50 POLYESTERCOTTON FABRICS TREATED WITH FLUORESCENTBRIGHTENER 125 The fluorescence value of a cotton sample crosslinkedwith triethanolamine in the pad bath was taken as 100%.

EXAMPLE 5 A cotton fabric was padded with a moist cure formu lation andthe moisture content was reduced to 7% using air drying conditions. Thefabric was sealed in a plastic bag and allowed to remain in the bag for24 hours at room temperature. The fabric was then laundered. The moistcure formulation was prepared using 13.5% dimethyloldihydroxyethyleneurea, sufficient hydrochloric acid to lower the pH to1, and the remain- 25 Samples of these fabrics were then treated with abath containing an acidic optical brightener (Fluorescent Brightener134). The procedure employed in Example was used in this case. Not onlywere the samples with the amine additive whiter under regular light butalso they were distinctly whiter than the. moist cure crosslinkedcontrol under UV light. Furthermore, when the samples were measuredusing the Farrand Spectro- TABLE vi fluororn eter, the results reportedin Table VI were ob tained. In this case, it is readily noticed that thesamples treated with the amine additives showed significantly betterabsorption of the acidic optical brightener than the control sampletreated with erosslinking agent and no reactive amine additive. Theeffectiveness of this process indicates that the use of a reactive amineadditive in finishing can be applied not only with standard pad-dry-curetreatments but also can be used in other finishing systems.

Samples of the moist cure fabrics were also padded with FluorescentBrightener 125 using the procedure employed in Example 3. Not only werethe samples treated with cross-linking agent and amine additive whitenerunder regular and UV light but Fluorescent values were significantlyhigher than the crosslinkcd control when measured using a FarrandSpectrofluorometer as listed in Table VII. Thus, while the moist curecontrol showed 6 percent of the fluorescence of the standard, the moistcure samples with reactive amine additives had values ranging from -78percent of the standard (in this case, pad-dry-cure sample with 9%DMDHEU and 5% triethanolamine in the pad bath. These results clearlydemonstrate that the overall process can be employed in a variety offinishing systems provided the basic concept is maintained throughout.

MOIST-CURE TREATED COTTON FABRICS TREATED WITH FLUORESCENT BRIGHTENER134 Untreated cotton control TABLE VII MOIST-CURE TREATED COTTON FABRICSPADDED WITH FLUORESCENT BRIGHTENER 7r Amine in Type of Amine in 72DMDHEUI Pad Bath Pad Bath Fluorescence 13.5, 0 None 5 13.5 1Triethanolarnine 13.5 1 Z-Dimethylaminoethanol 5 2 13.5 3Triethanolamine 66 MOlST-CURE TREATED CQTTON FAERICSJBEATEP WITHFLUORESCENT BRlGl-ITENER 125 Untreated control The pad-dry-cure sainplewith 9% DMDHEU and 5% triethanolamine additive was the standard given100% value in this case. Other members of the series are expw dmjm eutaebasis- Samples were given 'standard moist cure treat ment using061111765113; 'ir'aea'd'r'es;

and agentsas described in the beginning of Example 5.

EXAMPLE 6 Cotton fabrics were given an easy cure finish by padding thefabrics in a finishing bath, and then heating in a forced draft oven at60C. One fabric was heated for seven minutes and the other for nineminutes. The

finishing bath was prepared by using 13.5 parts dimethyloldihydroxyethyleneurea, 1 part hydrochloric acid and 85.5 parts water.Two other sets of fabrics were run in which 3% triethanolamine and 3% 2-dimethylaminoethanol were added to the finishing formulation togetherwith sufficient acid to reduce the pH to the same level as the controltreatment without additive. After these samples were washed, theyyielded two series (7 and 9 minute cures) of easy cure fabrics withamine grafts and appropriate controls. Samples of these fabrics werethen treated with an acidic optical brightener (Fluorescent Brightener134). The procedure employed in Example 1 was used in this case. Notonly were the samples with the amine additive whiter under regular lightbut also they were whiter than the easy cure control under UV light.Furthermore, when the samples were measured with a FarrandSpectrofluorometer using the conditions and the same standard samples asin Table V1, then the sample with the 7 minute easy cure treatment andno amine additive had 1 1 percent of the fluorescence of the untreatedcotton control. With 3% triethanolamine as an additive, the fluorescencewas 74 percent of the untreated control whereas with 3%dimethylaminoethanol as an additive the value was 68 percent of theuntreated cotton control. For the samples given a 9 ininute cure, thefluorescence values were 14 percent for the easy cure sample with noadditive, 60 percent for the easy cure sample with 3 percenttriethanolamine additive, and 69 percent for the easy cure sample withthe 2- dimethylaminoethanol additive. Thus, it is readily noticed thatsamples with the reactive amine additives showed significantly betterabsorption of the acidic optical brightener than the control samplestreated with crosslinking agent and no amine additives. These resultsagain serve to demonstrate the versatility of the process with otherthan the standard pad-dry-cure treatment.

Samples of the easy cure fabrics were also padded with FluorescentBrightener 125 using the procedure employed in Example 3. Not only werethe samples treated with crosslinking agent and amine additive whiterunder regular and UV light but fluorescent values were significantlyhigher than the easy cure control when measured using a FarrandSpectrofluorometer. Thus, with the series cured 7 minutes and (with theconditions and standard sample from Table VII), the

easy cure control with no amine additive had 6 percent of thefluorescent value of the standard. On the other hand, the easy curesample with 3% triethanolamine had 100 percent of the fluorescence asthe standard while the easy cure sample with 3% 2- dimethylaminoethanolhad 84 percent of the fluorescence of the control. These results clearlydemonstrate the favorable effect of the use of the amine additive inproducing a crosslinked fabric, which will absorb acidic opticalbrighteners from a pad bath. This represents another example of theeffectiveness of the overall process, irrespective of the particularfinishing system utilized.

We claim:

1. A process for imparting durable press performance and an affinity foran optical brightener to a cellulosic fabric subsequent to crosslinkingthereof, comprising:

a. impregnating a cellulosic fabric with an aqueous solution containingfrom about 1 -to 15 weight percent of dimethylol dihydroxyethyleneureaas a crosslinking agent for cellulose, about from. 0.5 to 4.0 weightpercent of an acidic reagent for catalyzing the crosslinking reactionbetween the fabric cellulose and said crosslinking agent, about from 0.2to 5.0 weight percent of an alcoholic amine selected from the groupconsisting of monoethanolamine, diethanolamine, triethanolamine, and 2-dimethylethanolamine, and sufficient acid to neutralize the vasicity ofsaid amine;

b. drying the impregnated fabric from step (a) at a temperature of aboutfrom 25 C. to C. for a period of about from 2 minutes to 24 hours;

0. curing the dry fabric from step (b) at a temperature of about from C.to C. for a period of about from 30 seconds to 20 minutes to effectcrosslinking of the fabric; and

d. treating the crosslinked fabric from step (c) with an acidic opticalbrightener.

2. The process of claim 1 wherein the alcoholic amine ismonoethanolamine.

3. The process of claim I wherein the alcoholic amine is diethanolamine.

4. The process of claim 1 wherein the alcoholic amine istriethanolamine.

5. The process of claim 1 wherein the alcoholic amine is2-dimethylethanolamine.

6. The process of claim 1 wherein the acidic catalist is zinc nitratehexahydrate. V

7. The process of claim 1 wherein the acidic optical brightener is ofthe Stilbene type.

2. The process of claim 1 wherein the alcoholic amine ismonoethanolamine.
 3. The process of claim 1 wherein the alcoholic amineis diethanolamine.
 4. The process of claim 1 wherein the alcoholic amineis triethanolamine.
 5. The process of claim 1 wherein the alcoholicamine is 2-dimethylethanolamine.
 6. The process of claim 1 wherein theacidic catalist is zinc nitrate hexahydrate.
 7. The process of claim 1wherein the acidic optical brightener is of the Stilbene type.